Devices for holding filters intended to stop particles in suspension in gaseous streams



March 14, 1961 R. P. F. DONGUY 2,974,749

DEVICES FOR HOLDING FILTERS INTENDED TO STOP PARTICLES IN SUSPENSION INGASEOUS STREAMS Filed March 5, 1958 United States Patent 0 DEVICES FORHOL-DING FITERS INTENDED TO STOP PARTICLES IN SUSPENSION IN GASEOUSSTREAMS Ren Pierre Francois Donguy, Vanves, France, assignor toCommissariat a IEnergie Atomique, Paris, France, a state administrationof France Filed Mar. 5, 1958, Ser. No. 719,305 Claims priority,application France Mar. 6, 1,957

3 Claims. ((1183-62) The present invention relates to devices vforholding filters intended to stop particles in suspension in gaseou'sstreams, and in particular in gaseous streams under pressure. Theinvention is more especially concerned with such devices for holdingilters intended to stop radioactive particles.

The chief object of the present invention Vis to provide k a device ofthis kind which is better Iadapted to meet the requirements of practice,and in particular which permits of easily replacing a used filter by anew one.

According to the present invention, this device includes twotubularsockets adapted to be xed in vgastight fashion on the respective endslof two portions of the circuit through which said gaseous stream isilowing, each of said sockets being provided witha central passageforming `an extension `of the vcircuit portion on which said socket isxed, said central passage forming an orifice in the face of saidlastmentioned socket located 'l Opposite-the other `of said f'sockets,the 'respective outer side walls of Lsaid two sockets ,being 'located ina common cylindrical surface, said two sockets being rigidly assembledtogether in line'with each other through means provided with "at leastone aperture suflicient to permit passage of a iilte'r therethrough,means operable from a distance being provided on 'at leastone ofsaidsockets for removably lixing a filter on said orifice ofV one ofsaid sockets so as tightly to apply the periphery of said orice againstthe edge of said orifice, a cylindrical Vsleeve being tted on the outerside walls of both of said sockets, said sleeve being slidable alongsaid sockets, whereby said sleeve can occupy either a position in whichit surrounds bothV of said sockets or a position in which it surroundsonly one of said sockets, and means being provided for sliding from adistance said sleeve with respect to said sockets. Y- v Preferredembodiments of the present invention will be hereinafter described withreference to the accompanying drawing, given merelyby way of Yexampleand in which: i Y

Fig. 1 is an axial vertical section of a filter holding device accordingto the invention, saidV device being;

shown in working position.

Fig, 2 is an elevational View of the same device'withl thecoveringsleeve lowered Vin order to permit replace- 2,974,749 PatentedMar. 14, 1961 Vice 2 to the filter and involves the risk of having himexposed to radiations or to cause him to absorb radioactive aerosols.Furthermore, such an operationV is often delicate since vthe mechanismfor opening the lter-holder must be provided so as to ensure a very goodlluidtightness, not only to the dust conveyed by the gas but also to thehigh pressure thereof.

lIn the embodiment of the present invention illustrated by the drawings,the filter-holder includes two sockets 4 and S in the form of cylindersof revolution xed, for instance by welding, on the ends of the portions2 and 3 of the gas circulation circuit.

rIhese two sockets 4 and 5 are rigidly assembled together by means ofelements 6 provided with apertures and constituted for instance byportions of a jacket in the form of a cylinder of revolution secured onsaid sockets d and 5 by means of screws 7 and provided with Wideapertures 8.

Of course, the whole of elements A4, 5 and 6 might be made of a singlepart provided with suitable apertures.

Filter 1 is mounted on a ring 9 one end of which is screw-threaded sothat it can be screwed on a cylindrical projection lil of socket 5(which is provided with corresponding screw-threads). The other end of`ring 9 is adapted to support the periphery of the lter i1 yand to applyit, in a dust-tight fashion, against a at annular joint 11 mounted in fasuitable housing of socket d.

'Ring 9 is advantageously provided withradi'al holes 12 diametrallyopposed.

The side walls of sockets 4 and 5 are provided with annular grooves inwhich are mounted toroidal-shaped packing members 13 intended to beapplied against the inner Wall of a sleeve 14 in the form of acylinderiof revolution the inner diameter of lwhich is substantiallyequal to the outer diameter of sockets 4 and 5, said sleeve 1-4 vbeingcapable of supporting the pressure of the gas tofbe treated.

The outer wall of sleeve 14 is Vprovided'with an annular projection 15provided with -a hole 16 parallel to the axis of said sleeve.

vvSleeve 14 is further provided with a longitudinal notch :17 capable ofguiding a pin 18 rigid with socket 4. It lfurther includes an abutment19 to limitits upward movement with rmpect to socket 5.

Sleeve 14 and socket 4 are provided with respective apertures 2t) and 21adapted to come opposite one another when the sleeve is in positionaround the two sockets. A key 22 can then be introduced into these holesso as to lock the sleeve in position on the sockets.

If it is supposed that initially the filter-holder is in this workingposition (Fig. l), the removal of a lter to be replaced by a fresh onecan be effected as follows:

The inflow of gas through conduit 2 is cut otl.L

Key 22 is removed.

The curved ends of two rods 23 are engaged into holes 16 and these rodsare pulled in a direction parallel to the axis of sleeve 14, whichcauses this sleeve to slide "with respect to sockets 4 and 5 and todisclose the aperof a` circuit through which circulates a gas underpres'- sure in which radioactive aerosols are in suspension.

It should tirst be reminded that, in theltering of such a gas (which mayfor instance .be the coolant gas "of a nuclear reactor, or `a gaswhichhad been in contact vis a dangerous operation becausetheir removalrequires the use of tools Ythe standard dimensions of which are drop ina suitable vessel.

relatively small, which compels the worker to be close turcs '8. The useof ya grease including some amount of silicon permits of ensuring a goodsliding of the sleeveV ,with respect to the sockets even at hightemperatures.

` A rod 24, of relatively great length, is inserted vthrough one ofthese apertures 3 into two corresponding radial apertures 12 of ring 9,and this rod is rotated about the axis of the ring so as to screw saidringon projection.V 10, which, releases the vi'ilter. y

It suliices then kto displace this iilter to cause it to yAll theseoperations can be effected without difficulty and by meansof very longrods, whereby the hands of the operator, and the operator himself, areat a distance such from the filter that the noxious e'ects thereof aresufiiciently attenuated. Y

The mounting of a new'filte'r is then obtained by efcting the abovementioned operations in the reverse or er.

At the end of the upward movement of sleeve 14, notch 17 engages lug 18so that holes 20 and 21 are in register and permit the introduction ofthe locking key 22.

4It should be noted that the device according to this invention gives avery good gas-tightness. In particular, the pressure of the gascirculating through the device cannot displace sleeve 14 because thispressure exerts a radial effort which is perfectly balanced.

However, the removal of the filter is very easy since the periphery ofsaid filter is not applied in a very strong manner against joint 11,this application being intended to ensure gas-tightness only for thevery small difference between the pressures existing on the Irespectivesides of the filter.

The lter may be made of any suitable material such as paper, glass woolor silica wool, sintered material, etc.

By way of example, it is indicated that a filter having a useful area of9 sq. cm. and a thickness of 4 mm., mounted on a support made accordingto the invention, was inserted in a gas circulation circuit where thepressure was 18 kg./sq. cm. No leakage was detected.

A particularly interesting application ofthe invention consists inintroducing a filter mounted in such a support in a conduit forcollecting the coolant gas from a nuclear reactor, upstream of acounting device, in order to stop the radioactive aerosols which mightdeteriorate some parts of said counting device.

'In a general manner, while I have, in the above description, disclosedwhat I deem to be practical and efcient embodiments of my invention, itshould be Well understood that I do not wish to be limited thereto as`there might be changes made in the larrangement, disposition and formof the parts without departing from 40 the principle of the presentinvention as comprehended within the scope of the accompanying claims.

What I claim is:

1. A device for holding la filter intended to stop particles insuspension in a gaseous stream, which device comprises, in combination,two tubular sockets adapted to be fixed in gas-tight fashion on therespective ends of two portions of the circuit through which saidgaseous stream is owing, each of said sockets being provided with acentral passagemforming an extension of the circuit portion on whichsaid socket is iixed, said central passage forming an orifice in theface of said last mentioned socket located opposite the other of saidsockets, the respective outer side walls of said two sockets beinglocated in a common cylindrical surface, means for rigidly assemblingsaid two sockets together in line with each other, said means beingprovided with at least one aperture sufiicient to permit passage of afilter therethrough in a direction transverse to the common axis of saidsocketsmeans operable from a distance on at least one of saidsockets forremovably fixing a filter on said orifice of one of said sockets so astightly to apply the periphery of said -filter against the edge of saidorifice, a cylindrical sleeve fitting in gas-tight fashion on the outerside walls of both of said sockets and slidable longitudinallytherealong, whereby said sleeve can occupy either a position in which itsurrounds both of said sockets or a position in which it surrounds onlyone of said sockets, and means operative from a distance for slidingsaid sleeve with respect to said sockets.

2. A device according to claim 1 in which the outer side walls of .saidsockets are provided with grooves, further including toroidal-shapedjoints inserted in said grooves and intended to be -applied against theinner wall of said sleeve.

3. A device according to claim 1 in which the means for removably fixingthe filter include a ring screwed at one end on one of said sockets and`adapted at the other end to support the filter and to apply it againstthe other socket.

References Cited in the file of this patent UNITED STATES PATENTS974,519 Reynolds Nov. l, 1910 991,572 Weisensten May 9, 1911 1,237,482Dalen Aug. 21, 1917 1,747,882 Prazmo Feb. 18, 1930 2,517,518 WilliamsAug. l, 1950 FOREIGN PATENTS 9,953 Great Britain Apr. 30, 1898 una

